1. Field of the Invention
The present invention relates to an apparatus and method that detect, for example, periodic body movement such as walking motion, and a content playback apparatus and method using the above apparatus and method.
2. Description of the Related Art
For example, for the purpose of counting the number of steps of a user, automatically recognizing a human action and movements, or providing the user with a sense of unity by matching the tempo of music with user's motion, it has become necessary to accurately detect a user's action (body movement), and various technologies concerning body movement detection have been proposed.
For example, Japanese Unexamined Patent Application Publication No. 02-161932 discloses a technology in which an acceleration sensor is used to detect body movement including walking motion and threshold-value-based determination is used to detect walking motion, and which relates to a pedometer having a mechanism in which appropriate threshold values can be set in accordance with variations of walking motion. Japanese Unexamined Patent Application Publication No. 10-113343 discloses a technology that recognizes actions by converting an acceleration sensor signal into a frequency-domain feature value and performing pattern comparison (pattern comparison of feature values) of the feature value with feature values stored beforehand in a form associated with actions.